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Dynamic Range Day - Loudness War Protest

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Why mp3s suck, and how to hear it

by Ian Shepherd

I hate mp3, and this post will tell you why.

DO NOT read this post if you have a large collection of mp3s, enjoy listening to them and can’t hear any problems with them, because it’ll ruin them for you !

There’s been plenty written on how mp3 works, and why lossy compression sounds worse than uncompressed audio in general. My aim here is to demonstrate how mp3 sounds bad, for all the people who keep telling me there’s no difference.

I’m going to give you clear guidelines and examples on what to listen for and the negative effects of mp3, but there’s no going back – once you can hear the problems, you’ll never stop hearing them.

This isn’t limited to audiophiles, or “golden ears”, by the way – in my opinion anyone can hear this stuff, with a few pointers.

So seriously, unless you’re prepared to start using Ogg Vorbis, FLAC or AAC - stop reading now !

Still here ? Good.

First, I need to make this clear – I have nothing against lossy audio or data compression in itself – I do most of my casual listening on an iPod, using 128kbps AAC files – they sound fine. Not as good as the original CDs, obviously, but OK. And yes, I’m well aware that AAC is just a more advanced version of mp3. But the fact is that mp3 has fundamental limitations – even at higher bitrates.

Next – I’m also a pragmatist. mp3 is a temporary phenomenon, just like AM radio, cassettes and CDs. In the long run, none of those have killed music, and neither will mp3, or lossy compression in general. So, why the rant ?

Because people keep saying mp3 sounds great, or “indistinguishable from CD” and it’s just not true.

mp3 isn’t good enough

It doesn’t matter what encoder you use, it doesn’t matter what settings you use or what pre-processing you apply – mp3 just doesn’t cut it. AAC and later, more sophisticated encoders use more advanced encoding methods, and sound better to varying degrees, but mp3 just FAILs.

How does it fail ? That depends a little on the encoder being used, but some of my own pet hates include:

  • mp3 sizzle – the artificial, unnatural swirling metallic noises that sound like someone’s added chime bars to everything, or there’s a mosquito buzzing in your ear. Some people actually say we prefer these noises in mp3s – I say bullshizzle !
  • Added distortion – Yet another side effect of the so-called Loudness Wars. mp3 encoders rarely include any headroom for the encoding process itself, so the added processing pushes the music even further over the limits, generating inter-sample peaks and adding even more distortion in the process
  • Flat, two-dimensional sound mp3 works by throwing away musical information that we supposedly can’t hear – up to 90% of the original information, at 128kbps. That means all the subtle, delicate stuff, like ambience, space and realism. So a lush, three-dimension original is reduced to a flat, cardboard replica of itself
  • Mushiness All but the very best mp3 encodes just sound fuzzy, muddled and – well, mushy !

Hear for yourself

Don’t take my word for it – here are some examples. First, a truly nasty 128kbps mp3 example, from a Deep Purple live album I mixed a while back:

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(Before anyone jumps on me, I’ve heard even a 256 kbps mp3s sounding like this – I’ve just used a low quality version to make the point.)

If that doesn’t sound too bad to you at first, try this - I’ve filtered the file to highlight the high frequencies. You can hear the problems most clearly when the vocals start:

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Some people describe this effect as “sizzle”, or “swirlies”. It’s not just that I’ve removed all the bass, what I’m pointing out is the unatural bubbling, twinkling “chime-bar” type sound, or as my friend and fellow mastering engineer Nick Watson once called it, the “flocks of tweeting ultrasonic birdies”. It also reminds me of someone crinkling up tin foil !

Once you’ve picked it out, listen the first version again. Doesn’t sound so nice now, does it ? Can you ignore the swirlies, now you know they are there ?

Now download and listen to the original file:

‘Talk About Love – Excerpt’ – 5 MB WAV file

Listen to the clarity, punch, and bite of the WAV, compared to the swirly, soggy mess of an mp3. Which one do you prefer ?

The loss of depth, richness and three-dimensionality is more subtle side-effect, but just as unfortunate. Here’s a snippet of a recording I did for the brilliant Hans Koller, featuring Christine Tobin on vocals:

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(This is a much better mp3 encode, with far fewer heinous swirlies. But still…)

Here’s the WAV version:

‘The Great Bear And The Small – Excerpt’ – 11 MB WAV File

Don’t expect the difference here to leap out at you straight away, it’s more a case of feeling it – listen to the swirls of the harp from 30 seconds in, listen to the piano and Christine’s voice – on the wav file, there’s a warmth, and a depth, and a sparkle that in the mp3 has just gone.

Listen to the wav several times over, then switch to the mp3. Do you honestly feel it sounds as good ? The mp3 is OK, but it’s just… meh. I’m not drawn in, my attention wanders, it doesn’t move me.

Something essential has been lost, and you can’t get it back. And once you’ve heard that loss, even cranking the data-rate up doesn’t help. The only solution is a more advanced format, or lossless files.

Try listening to the mp3s in your music collection. Go back and compare them to the CDs you ripped them from.

…Sorry.

Update: I’ve had lots of interest in this post, and lots of discussion, especially on link-sharing sites. There are a few common responses that I want to answer here.

No-one uses 128 kbps mp3s

Wrong. If you’ve made this comment, you probably already know about LAME and the all other flavours of mp3 codec, and you probably do choose to use higher bit-rates, but you’re in the minority. Most “regular listeners” go for the default settings – and even in iTunes this is only 160 kbps.

192/320 kbps sounds fine

Sometimes. This depends so heavily on the material, the encoder and the codec – you simply can’t make blanket assumptions. Ironically one of the factors that makes mp3 so popular – the fact that there are so many encoders and players, some of which are free – also makes it far harder to get a decent encode. By contrast, the grip Apple have over the AAC format at least ensures consistently high standards of encoding.

You’re just an Apple fanboy

No. Well alright, yes – I am a big fan of Apple’s products, but there are plenty of other alternatives to mp3 – OGG Vorbis, FLAC etc. The only reason I mention AAC a lot is it’s a format I have deep experience of, and always sounded good (but not perfect !) to me.

And another thing

To everyone who keeps saying “just use 320 kbps”, I say – why ?!? mp3 simply has inherent limitations compared to other formats. The whole point of lossy audio is to save space. At 128 kbps that saving is 90% – well worth having. At 320 kbps though, that saving is only 60% and it still doesn’t sound great – I’d rather go with FLAC or Apple lossless, which can often achieve a 50% saving, and have something that sounds every bit as good as the source.

Image by Roger B

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181 Responses

  1. Phredreeke says:

    Well iPod suggests portable listening and most people have lower demands for that than more “serious” forms of listening. It doesn’t have to be “true to the original” just “good enough to listen to”.

    As for AAC it stays “good enough to listen to” for very low bitrates.

    I think however that Ian’s problem with this isn’t what people listen privately to on their iPods or Sansas or whatever music player you use, it’s your choice what codec to encode with and at which bitrate. The problem is that music are being sold already encoded in MP3 formats which means that someone else already made the choice for you.

  2. Nobunaga says:

    Not to kick up an old thread here, but AACs and OGGs aren’t that much better. That don’t really produce the sizzle, but they’re just as flat because they compress music the same way.

  3. Charlie B. E. says:

    What I HATE about the MP3 format, is that starting during the `00s, and increasingly thus far throughout the “20-teens” era, Rock and Pop artists have “mixed” their music so as to still sound alright on the highly compressed and crappy MP3 format. ALL contemporary music these days just sounds “loud and blaring”; without anything akin to the dynamics and naunce that music USED to have, especially during the `70s, but also during the `80s, and 90s. Everyone, even Country and “soft Pop” artists, “mix” everything to sound LOUD. If a person plays such music at “normal” volume levels, it sound blaring; and if you play it at a lower level, it just sounds “dull”.
    ~ Personally, I can`t wait until the increasingly tiny and affordable “storage medium” revolution gives us iPod type devices with Gigabytes-worth of data storage space, so that common people can download large amounts of songs in WAV file, or Direct Stream Digital encoding format. THEN the artists can resume using dynamics in the recorded performances, like music SHOULD BE.(Anyone that may have any “inside information” on how or when this developement may be occuring, please do reply to this comment.)

  4. Mark says:

    Just to stir things up a bit. I am a musician with a home studio. I record music in wav format at 32 bits and 44100 Hz. I listen on studio monitors 1 meter away from my ears mounted on insulated stands in a room with sound absorption to reduce unwanted reflections. I spend hours finding exactly he sound I want.

    But when I am not recording music I listen to my collection on mp3. I have ripped all my CDs to mp3 and chucked the originals. I carry a Creative Zen around with all my music on and I love it.

    The important point here is how the mind and ears work together. I know all the records in my collection very well, I love them. So I don’t need perfect, or even very good, reproduction to enjoy them. I just need enough to remind me how they sound and the incredible instrument that is the brain fills in all the rest.

    Sure I listen to new music in good quality, but once I know a song mp3 is plenty good enough for me!

  5. Matt says:

    Please kill me before AAC or ALAC become new mediums of sound. I prefer my music without blaring corporate watermarking from a terribly restrictive iTunes service, thank you very much.

    But aside from that, I’ve shown these examples to a few friends in their mid thirties and fourties. All of them have been able to pick out these correctly, among other web-based tests, in a matter of four seconds with mid-range equipment. Even the MP3 – FLAC difference test is blaringly obvious to most of the people in question. I have no doubt that this is going to prove less successful with a younger crowd, even with their more dynamic reception of the frequency band.

  6. Ray says:

    For the Talk About Love example, the wav is also lacking in a rich sound stage and dynamic range — That’s much worse to me than the swirlies. I guess what I am challenging is — would better mixes come out more acceptably through the compression process, esp if they’re at >= 320 kbps?

    Also, can swirlies be attentuated on decode?

  7. Ian Shepherd says:

    Hi Ray,

    More dynamic, open music often survives encoding better, because the encoder has to work “less hard”, and so has “more to work with”. However mp3 just don’t do as good a job as more advanced codecs – an AAC of that track can sound pretty good (and to be fair, you can get better mp3 encodes of it, too.)

    Higher bit-rates almost always help, but really why bother, these days ?

    I’m not aware of “swirly reduction” decoding, but such processing will always have further side-effects, like attempts to remove “mosquitos” from jpeg images, for example. At the end of the day, once the information is gone, it’s gone…

  8. Ian Shepherd says:

    @ Matt – actually young people also prefer high-quality formats:

    http://productionadvice.co.uk/listeners-can-hear/

  9. Jared says:

    I agree that mp3 is not the best format for compressed music however it is the only format that I know that works in both itunes and windows media player. I need a format that allows me to play music on my smart phone and my ipod touch and my computer easily without having to hunt down third party plugins and other forms of manipulation.

  10. LeFnorZ says:

    To my knowledge mp3 is not necessarily “free” and far from being open-source: https://en.wikipedia.org/wiki/MP3#Licensing_and_patent_issues

  11. Daniel says:

    I listen to 320CBR for the time being. When media players support .flac or .ogg and when bigger flash memory becomes an option, I’ll make the switch.

  12. Peter Pan says:

    Every mp3 has a tiny bit of silence at its beginning, resulting from the conversion process. Just listen to a live CD converted to mp3, you will always hear that gap on every track transition, which ruins the “live experience” for me if you know what I mean. People alway comlain that flac and the likes are inconvenient formats for their iPod/iPhones etc., in fact they just need a proper audio player software that supports the format, or get the right plugin or in the case of apple use apple lossless etc. most of the stuff is free and easily to find if you know how to make use of google.

  13. Roger says:

    My two cents…

    I would like to know how many people actually tried an ABX test with a properly encoded LAME (V0) vs the original Wave. I’m talking about ABX because you’re listening without KNOWING if you’re listening to “A” or “B”.

    There’s no excuse not to try this, and I’m sorry, but I can “distinctly” hear the difference between two power cords… …when I’m looking at it!

    This is not to say that even a properly encoded mp3 isn’t going to lose sound quality to the original (it will always happen), but many of these artifacts are clearly outdated or present on lower bitrates/worse encoders (btw, I’m sorry, but using iTunes to encode mp3 is NOT the best option).

    I never bought a single song on iTunes or another paid download service.

    In 2013, I feel that it makes no sense in buying lossy compressed tracks anymore.
    I’d rather buy the original CD (which I can then compress to my format of choice, be it lossy or lossless), which is somehow obvious if we consider that sometimes it isn’t more expensive.

    But my format of choice is lossless music downloads like HDTracks and similar services.

    Many of these recordings are better not only because of the greater definition of the format, but also because it is mastered with different goals in mind (compared to the CD version), and it usually has a lot more dynamics.

    Take the latest album from Muse as an example, and you don’t even need to actually hear it. Load the 2 versions of same song in your fav audio editor and the greater dynamics are pretty clear.
    It’s also a pointer to the fact that the CD version could also have (a lot) more dynamics.

    The mp3/aac is all about portable sound. The same 16 GB iPod filled with music at ~200 kbps is going to hold a lot more music than if we use ALAC versions.

    It’s debatable if most listening conditions on a mobile device will ever give real benefits between these two compression examples.
    It’s very easy for the outside noise and earbuds quality to have a greater impact than the one given by a V0 LAME encoded mp3.

    But I wouldn’t (and I don’t) use 128 kbps bitrates for pretty much anything, portable devices included.

    And most importantly, iTunes is only going to see my money on music if they release lossless compressed tracks in the future.

    Coming back to where I started, I strongly suggest an ABX test with the best versions of LAME mp3 encoding.
    I won’t say that you’ll start loving mp3 sound, but it can definitely put things in perspective.

    If one really wants to hear, one must close the eyes and other input devices besides the ear.

    Cheers

  14. Mr Pellaeon says:

    Personally I hope MP3 format just dies off within the next 5-10 years kind of like how it took a hell of a long time for the VHS format to die off. I have my personal music collection in Ogg Vorbis format using the latest version of the Xiph.org encoder from Feb 2012 and at the setting I use which is -Q9 I can honestly say in comparison to old MP3 tracks I had of same songs ten years ago the difference in quality with Vorbis is like a huge breath of fresh air. In short it blows MP3 out of the water.

    It also doesn’t help that since 1991 when MP3 came out there has been a glut of horrible MP3 encoders over the years such as Xing and Qdesign didn’t help. LAME improved upon it and is still updated even in 2013 but it’s still has to follow the inherent limitations of the MP3 format.

    In regards to Android phones I know with alternate music players on 2x and 3x firmware devices/tablets you can play Vorbis and flac files with no problems, 4x supports OGG in the default music player, and with iPhones/Ipods/ipads running iOS 4.3 or later you can use a music player called Capriccio that allows you to actively bypass iTunes to transfer over OGG Vorbis/flac files via Wifi or FTP transfers to the device.

  15. born in 80 s says:

    people who never heard sound of R2R stereo or vinyl really think that listenn to musical sawnd-mp3.

  16. Sir Ellis says:

    People who say MP3 sounds as good as a CD or vinyl are like people who say a £2.99 bottle of wine is as good as one that’s £15. I say keep drinking the crap and leave the good stuff to us…

  17. dadude says:

    Do a blind test between 256 kbps VBR MP3 and CD-quality lossless then. The difference isn’t nearly as big as you describe it to be…

    Wine was probably the most pathetic analogy to relate to too.
    http://www.wellesleywinepress.com/2009/05/charles-shaw-blind-tasting-or-are-we.html

    Vinyl is mastered differently from CD and is inherently a flawed medium of playback so you can’t really compare the two in the first place.

  18. I have an old friend who loves music, classical and popular and he downloads vast amounts of stuff from the www. I say to him “If you love music why would you subject yourself to such bad sound quality , bereft of humanity , dynamics, detail and musicality?” He knows I am an audiophile vinyl nut but regardless, how is it that a whole generation of people don’t even own a cd or record player and some decent speakers and think playing music through their mobile phones via tiny ‘ear buds’ is satisfactory? . I think it is quality versus quantity.
    It is his / their loss. Music sounded better when it was recorded on audio tape and pressed onto vinyl . The digital remasters I am hearing of Van Morrison( Into the music ), The Beatles( the shite album), Brahms( clarinet quintet), The Band ( The Band ) and so on have all been ‘brickwalled’ and do not sound anything like the true original recordings.I can’t dig remastered recordings at all
    MP3 ‘s are even worse! .

  19. dadude says:

    Again, blind test between 256 kbps VBR MP3 and CD-quality lossless and I can pretty much guarantee you won’t hear a difference between the two. You can’t say it’s worse if you can’t hear the difference.

    “…so on have all been ‘brickwalled’ and do not sound anything like the true original recordings”
    Often times the digital remasters of albums are terrible and are affected by the “loudness war” effect. A lot of them do indeed sound just plain bad.

  20. Derek says:

    128kbs aac sounds garbage through a hifi, it’s not subtle. 320kbs lame (slow-high setting) mp3 however sounds close to a CD and certainly better than the 256kbs aac crap that iTunes sells (played through a hifi) and yes I’ve done blind tests. The sound from aac doesn’t do it for me. 320kbs ogg sounds better than lame though.

  21. Ian Shepherd says:

    Interesting, how did you set up your blind test ? iTunes is a pretty good encoder, in my experience – it beats mp3 @ 320 kbps hands down

  22. dadude says:

    Don’t forget that AAC is technically superior to MP3s of the same bit rate.

  23. Marcin says:

    and ogg aotuv -q9 vs aac ~320? What’s your expierience? I’m using ogg -q9 and I’m pretty satisfied.

  24. Phredreeke says:

    I can’t tell a difference between MP3 or AAC or Ogg Vorbis or Opus at high bitrates.

    I can’t remember what bitrate I used when I tested, but I think it was 48 or 56 kbps. MP3 was as bad as expected, lacking any high end. HE-AAC was generally good except for drum hits which had an annoying “sucking” sound. Ogg and Opus was very good, although still discernible from the original.

  25. Manu says:

    I love Classical music and Opera where you find more than a hundred musicians (and singers) playing at a time,.. so, you need detail clarity and a good sound space.
    Loosles encoders are the thing,….(“more if you pretend hearing your music at your place,”)
    …. WAV is great but far too big in size, so the second best option for me has been FLAC,,….so you can record on WAV and then make the change to FLAC,….the “VLC” (free)audio programm is great and supports FLAC.

  26. guest1 says:

    It is true: do not use mp3 @ 128kb/s. However, if it’s for space, use $lame -V1 or V2. I download classical music only in FLAC though.

  27. Appreciation to my father who stated to me on the topic of this website, this weblog is really amazing.

  28. Ciprian says:

    My friend, first of all you don’t even know the basics on how digital music is analogized by a sound card, you didn’t even specify what sound card are you using to make those assumptions not to mention the 2nd dimension of a digital file which is the “bit depth” If your sound card is set to 16bit you cannot hear even wav files at the most top quality. Listening an audio CD will bypass the DAC conversion and will output the highest quality. Ihave all my mp3s encoded at 320kbps with 24 bit depth and I can hear the sharpest bird chip. First of all by a dedicated sound card that suppoer 24 or 32 bit dip output and rewrite this article

  29. Ian Shepherd says:

    Wow, there’s so much wrong with what you said there I don’t even know where to start.

    You realise I mixed and mastered the examples in this article myself ? One of them I recorded ? All using 24-bit gear ?

    “Analogized” isn’t even a real word… Enjoy your 320 kbps bird chirps :-)

  30. Jonny says:

    320kb bird cheeps? Must be the new album from Tommy Wiseau..

  31. J says:

    How come when people say they can hear a difference between 320mp3s and HD wav files they won’t actually prove it with a blind listening test?

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Ian Shepherd


BBC Radio 4 Interview

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Ian Shepherd from Production Advice discusses the Loudness Wars

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